Vehicle and Power Unit For It

ABSTRACT

The invention relates to a vehicle comprising at least one electromotor for driving the vehicle, an actuator for controlling the supply of electric power to the electromotor and a power system for providing electric power to the electromotor drive of the vehicle, which power system is provided with first energy storage means for storing a quantity of energy and having a power discharge capacity, first measuring means for measuring the energy condition of the first energy storage means, first power generating means for generating electric power, a computer system, operationally connected to the actuator for receiving a power demand, to the first measuring means for receiving a first energy condition value, and to the first power generating means, wherein the first energy storage means are operationally connected to the electromotor for supplying power thereto, the first power generating means are operationally connected to the first energy storage means for supplying energy thereto, and the computer system controls the power supplied by the first power generating means so that the energy storage means are able to provide the electromotor drive with the power the electric drive needs for driving the vehicle.

BACKGROUND OF THE INVENTION

The invention relates to a vehicle comprising an electromotor fordriving the vehicle and a drive system, particularly a so-called hybriddrive system.

Many vehicles driven by electromotors are provided with a device forgenerating electric power or energy, such as a generator, solar panelsor fuel cells. In addition devices are usually present for storingelectric power or energy, such as batteries, chargeable batteries,capacitors, or the like. Usually the generator is then operationallyconnected to the electromotors in order to provide them with electricpower, the surplus being supplied to the batteries.

A drawback is that the various demands the individual components makeare not optimally dealt with. On the one hand this causes energy lossand the life span of the components may be affected, or as the occasionarises it may cause damage to the components.

For instance US-A1-2004/0065489 describes a fuel cell driven vehicle. Asaccording to said publication a fuel cell is not considered capable offor instance complying with the large changes in power demand, an energystorage in the form of batteries is provided for. The fuel cell thusprovides the electromotor with power to drive the vehicle, and forinstance a battery temporarily provides the electromotor with additionalpower in order to cater for the changing power demand. As a result thefuel cell having an actual overcapacity is installed and the battery isdisadvantageously burdened.

SUMMARY OF THE INVENTION

It is an object of the invention to at least partially overcome saiddrawbacks.

To that end the invention provides a vehicle comprising:

-   -   at least one electromotor for driving the vehicle;    -   an actuator for controlling the supply of electric power to the        electromotor and    -   a power system for providing electric power to the electromotor        drive of the vehicle, which power system is provided with:        -   first energy storage means for storing a quantity of energy            and having a power discharge capacity;        -   first measuring means for measuring the energy condition of            the first energy storage means;        -   first power generating means for generating electric power;        -   a computer system, operationally connected to the actuator            for receiving a power demand, to the first measuring means            for receiving a first energy condition value, and to the            first power generating means,            wherein the first energy storage means are operationally            connected to the electromotor for supplying power thereto,            the first power generating means are operationally connected            to the first energy storage means for supplying energy            thereto, and the computer system controls the power supplied            by the first power generating means so that the energy            storage means are able to provide the electromotor drive            with the power the electric drive needs for driving the            vehicle.

By choosing for a mutual connection of the energy sources and powersuppliers in the manner according to the invention and a computer systemfor control, the energy use can be minimised and the advantages of eachcomponent can be utilised better.

It will be clear that electric (input) power follows directly from thevoltage and the amperage. If the voltage in the vehicle is keptconstant, the amperage can be considered a measure for the input powerand when the amperage is kept constant the voltage can be considered ameasure for input (electric) power. The energy then is the powersupplied during a period of time.

In one embodiment of the invention the computer system controls thepower supplied by the first power generating means in order for thefirst energy condition value not to drop below a set first thresholdvalue.

In an embodiment of the vehicle according to the invention, it furthercomprises second energy storage means, preferably capacitors, preferablycomprising several capacitors each having a capacity of at least 800 Fand having an energy storage capacity of at least 2 KJ, operationallyconnected to the first energy storage means for receiving electric powertherefrom or supplying electric power thereto. Said second energystorage means are especially added for supplying high power during ashort period of time, for instance for accelerating.

In an embodiment the vehicle further comprises a charging deviceconnected between the first power generating means and the first energystorage means.

In one embodiment of the vehicle it further comprises a control device,connected to the first energy storage means and the charging device.

In one embodiment the vehicle further comprises several first energystorage means, parallel interconnected.

In one embodiment the vehicle comprises several second energy storagemeans, each second energy storage means being connected to one of thefirst energy storage means.

In one embodiment each first energy storage means comprises its owncharging device and its own control device.

In one embodiment the first energy storage means are adapted forgenerating direct voltage. In this way no converter is necessary betweenthe energy storage means and the power generating means.

In one embodiment the first power generating means are parallelconnected to the first energy storage means.

In one embodiment the first energy storage means or the several energystorage means are each connected via a converter with a solar panel.

In one embodiment of the vehicle the electromotor is a synchronous motorhaving permanent magnets, provided with a control system for controllingthe operation of the electromotor within the electromotor.

In one embodiment of the device the first energy storage means compriseat least one battery.

In a further or alternative embodiment the power generating meanscomprise a generator preferably provided with a combustion engine.

In a further embodiment the vehicle is further provided with at leastone wheel that is directly driven by means of the electromotor,preferably an electromotor in the wheel, particularly a wheel asdescribed in WO-A1-01/54939, of which the description and figures shouldbe considered fully incorporated in this application.

The invention further relates to a vehicle, a power system and method asdescribed in further independent claims and sub claims dependentthereon. Optionally divisional patent applications may relate to theembodiments described therein.

According to another aspect the invention further relates to a vehiclecomprising:

-   -   at least one electromotor for driving the vehicle;    -   an actuator for controlling the supply of electric power to the        electromotor and    -   a power system for providing electric power to the electromotor        drive of the vehicle, which power system is provided with:        -   a first energy storage for storing a quantity of energy and            having an electric power discharge capacity;        -   a first energy meter for measuring an energy condition of            the first energy storage;        -   a first power generating unit for generating electric power;        -   a computer system, operationally connected to the actuator            for receiving a power demand, to the first energy meter for            receiving a first energy condition value therefrom, and            connected to the first power generating unit,            wherein the first energy storage is operationally connected            to the electromotor for supplying power thereto, the first            power generating unit is operationally connected to the            energy storage for supplying power thereto for supplementing            the energy, and the computer system controls the power            supplied by the first power generating unit so that the            energy storage is able to provide the electromotor drive            with sufficient power for driving the vehicle.

The computer system is able to activate the power generating unit aslong as the first energy condition value is below a set first thresholdvalue.

Said vehicle may also further be provided with a power meter formeasuring a power condition of the first power generating unit, whereinthe computer system is furthermore operationally connected to the powermeter for receiving a power value therefrom, and the computer systemfurther sets the power supplied by the energy-generating unit to theenergy storage adjusted to the power value.

According to another aspect the invention relates to a method forcontrolling the electric power for an electric drive of a vehicle,wherein a first energy storage supplies electric power to the electricdrive, a first power generating unit supplies electric power to thefirst energy storage, and wherein an energy condition of the firstenergy storage determines the power to be supplied by the powergenerating unit.

According to another aspect the invention relates to a power system forsupplying electric power to a vehicle having an electric drive, whereinan energy condition of a first energy storage unit determines theelectric power to be supplied by a power generating unit to the energystorage unit.

In particular a power discharge capacity of the first energy storage maydetermine the power discharge capacity of the power system.

More particularly the power discharge capacity of the first energystorage may almost correspond to the power discharge capacity of thepower system.

According to another aspect the invention relates to a vehiclecomprising an electric drive, preferably comprising at least oneelectromotor, having a peak input power and a rated input power, anaccumulator unit having an energy storage capacity and a power dischargecapacity sufficient for supplying the peak input power during a timespan necessary for accelerating from a standstill to a cruising speed ofthe vehicle, and a generator provided with a combustion engine having arated power discharge approximately corresponding to the rated inputpower of the electric drive.

In that case the energy storage capacity of the accumulator unit may besufficient for providing the electric drive of the vehicle withsufficient power for maintaining the cruising speed during avehicle-specific driving time.

The vehicle-specific driving time may at least be 15 minutes, preferablyat least 60 minutes.

According to another aspect the invention relates to power system forproviding an electric drive of a vehicle with electric power, comprisingan energy storage provided with an energy meter for measuring an energycondition of the energy storage, and a power generating unit providedwith a setting unit for setting the electric power to be supplied by thepower generating unit, wherein the energy storage supplies electricpower to the electric drive, the power generating unit supplies electricpower to the energy storage, and the setting unit is operationallyconnected to the energy meter and sets the electric power to be suppliedby the power generating unit to the energy storage on the basis of theenergy condition of the energy storage.

The setting unit may in that case be connected to the energy meter viathe computer system that controls the setting unit.

According to another aspect the invention relates to a vehiclecomprising:

-   -   at least one electromotor for driving the vehicle;    -   an actuator for controlling the supply of electric power to the        electromotor and    -   a power system for providing electric power to the drive of the        vehicle, which power system is provided with:        -   first power storage means for storing energy for supplying            electric power;        -   first measuring means for measuring the power condition of            the first power storage means;        -   first power generating means for generating electric power;        -   second measuring means for measuring the power condition of            the first power generating means;        -   a computer system, operationally connected to the actuator            for receiving a power demand, to the first measuring means            and second measuring means for receiving first and second            energy condition values, and to the first power generating            means,            wherein the first power storage means are operationally            connected to the electromotor for supplying power thereto,            the first power generating means are operationally connected            to the power storage means for supplying power thereto, and            the computer system activates the power generating means as            long as the first power condition value drops below a            predetermined first threshold value.

Optionally the aspects mentioned in this description may be used incombination for further improvement.

SHORT DESCRIPTION OF THE DRAWINGS

The invention is further elucidated on the basis of an exemplaryembodiment of electricity for a vehicle according to the invention, inwhich:

FIG. 1 shows an electricity diagram for a vehicle according to anembodiment of the invention;

FIG. 2A-2C show a diagram of the energy consumption of a known fuelcell-driven vehicle in comparison to an embodiment of a vehicleaccording to the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a drive system diagram for a drive system according to anembodiment of the invention. In this figure the dot and dash lines areAC-connections, the interrupted lines are data connection lines and theuninterrupted lines are DC-supply lines.

In FIG. 1, the wheels provided with an electric drive are indicated by401, which wheels are for instance described in International patentapplication WO-01/54939, and also the wheel struts 412 are describedtherein connected in a vehicle. In order to supply input to the wheelsthe vehicle is provided with a computer system 422 and back-up computersystem also indicated by 422. In addition input means 409 are providedby means of which a driver of the vehicle is able to enter data anddrive the vehicle. The vehicle is provided with very many energy sourcesnamely for the short term, for the medium term and for the long term.

For the short term the vehicle is provided with elements 402 forsupplying very high power during a very short time. Such devices mayparticularly comprise so-called super capacitors, that means capacitorsof a very high capacity. Preferably said device comprises capacitorshaving a capacity of at least about 800 F each. Such capacitors eachsupply approximately 2.5 V of voltage. According to the inventionapproximately 160 of such capacitors are used for supplying 400 V. Suchcapacitors are available up to a capacity of approximately 5000 F. It isof importance that the power stored in the capacitors can be supplied ina short time, usually several seconds, for accelerating the vehicle.

The vehicle as described is furthermore provided with sources forsupplying power at the medium term, indicated by 403. Such power sourcesmay for instance be batteries.

In addition a vehicle having an energy system according to the inventionmay be provided with energy generators for the very long term. Thismeans for instance generators, namely conventional generators such adiesel engine, fuel cells or the like, that convert a fuel into electricpower. Preferably said generator supplies direct current, so thatbatteries can be immediately charged.

The vehicle is furthermore provided with an external generator forgenerating electric power, such as for instance a solar panel. Such apanel is optional.

The vehicle is furthermore provided with a converter for converting theenergy from the solar panels into the desired voltage. Said convertersare indicated by 406. The vehicle is furthermore provided with batterychargers 407 and a battery control system 408. In addition a reclaimsystem for the brake energy is provided, in this case parts 410 and 411(brake energy chopper and brake resisters). Optionally the vehiclemoreover comprises generators for reclaiming heat from exhaust gassesand reclaiming heat from the liquid cooling system. Said elements areindicated by 413 (generator reclaiming system for the exhaust gases),414 (generator for the liquid cooling liquid), 415 (generator for heatexchange with the liquid cooling), 416 (heat exchanger for the coolingliquid of the electrically driven wheels), respectively. For pumping thecooling liquid around for the driven wheels, the vehicle is providedwith a liquid pump 417.

The vehicle is furthermore provided with a DC-DC converter for providingpower to the sub-systems for the vehicle. Said converter is indicated byreference number 418, and is provided for converting the battery poweror the other voltages into voltages that are suitable for systems todrive the vehicle. The vehicle further comprises a so-called auxiliaryfor battery for vehicle sub systems 419 and a connection 420 for theexternal power grid.

Furthermore a three-way valve is provided for cooling liquid 421 and aDC-DC-converter for the generator indicated by 423. The vehicle isfurthermore provided with various radiators for the cooling of coolingliquid indicated by 425.

What is so special about the electric system of the vehicle specificallydescribed here is the way in which the various power sources areinterconnected. For instance the so-called super capacitors 402 that arecapable of supplying a very high power for a very short time, forinstance for accelerating the vehicle, are connected to batteries. Via abattery control system the batteries are directly connected to thewheels and wheel struts in order to supply power to them. The generator404 (or fuel cells for instance), is not directly connected to thewheels and wheel struts here, that means not directly to the powerconsumers, but is connected to the batteries via the chargers 407. Inthis way the vehicle can be divided into power consumers, that means thewheel struts, the internal vehicle systems and the wheel struts, andvarious sources of electric power, that means the very short termsources, the medium term sources and the long term sources.

In the embodiment according to the invention the medium term sources,that means for instance the batteries, are directly connected to thepower consumers. The other power sources are indirectly connected to thewheels via the energy sources for the medium term, that means forinstance the batteries. For instance there are solar panels 405 which bymeans of converters 406 are connected to the batteries, so-called supercapacitors for supplying high power during a very short period of time,indicated by 402 and connected to the batteries, and in this way thebrake power energy reclaiming systems 411 are also connected to thebatteries via converters 410. Also the generator or fuel cell or thelike 404 is connected to the batteries via chargers 407. Each battery isfurthermore provided with a battery control system 408 that monitors thepower and the desired power of the batteries and at the right momentadds the correct additional power source or gives a warning when one ofthe energy sources does not have enough power.

FIGS. 2A-2C show an energy consumption diagram of a known fuelcell-driven vehicle in comparison with an embodiment of a vehicleaccording to the invention. FIG. 2A shows a table with a time path withrandom units 1-60. Column 1 shows the amperage that a battery in avehicle according to the invention should for instance supply to anelectromotor in order to drive it. Column 2 shows the amperage that thegenerator supplies during the entire path. Said amperage level is basedon historical information regarding the driving behaviour of a vehiclefor instance obtained via measurements. In that way it can be determinedwhat a usual driving time is, and the related overall electric power tobe supplied by a generator.

Column 3 shows the power to be supplied by a battery for the same drivepath in case of a fuel cell-driven vehicle, such as for instancedescribed in the above-mentioned US-A1-2004/0065489. Column 4 of thetable gives an example of an amperage to be supplied by the fuel cell.The column on the far right shows in shades the various drivingsituations, consecutively: accelerating, constant speed, braking,standing still, accelerating, constant speed and braking.

FIG. 2B shows a graph of the amperage supplied by the battery and thefuel cell, respectively, that were shown in the table of FIG. 2A. It canclearly be seen that the battery is activated when the power demandsuddenly rises, and is charged during regenerative braking, wherein anelectromotor connected to the wheels of the vehicle functions as adynamo and generates energy. In this configuration only a smallinstalled power worth of batteries needs to be installed. However astrongly overdimensioned fuel cell needs to be used.

FIG. 2C shows the same driving path as FIG. 2C, in this case, however,for a vehicle according to the invention. In this case the batterysupplies the actual power to one or more electromotor(s), and thefluctuations in the power demand can be largely compensated. Asexplained before regarding FIG. 1 ultra fast power suppliers such as“super capacitors” or even “ultra capacitors” may ensure a short energyboost.

The generator in this case supplies a constant power. When the battery,which controls the actual power demand to the generator, is fullycharged it will be able to entirely switch off the generator. It is evenpossible that the power condition of the battery (set) controls a powermodulation of the generator. Please note that in this case as well theamperage during braking is below zero as use is made here ofregenerative braking, that means that when slowing down a vehicle adriving electromotor functions as dynamo.

It will be clear that the above description is included to illustratethe operation of preferred embodiments, and not to limit the scope ofthe invention. Starting from the above explanation many variations thatfall within the spirit and scope of the present invention will beevident to an expert.

1. Vehicle comprising: at least one electromotor for driving thevehicle; an actuator for controlling the supply of electric power to theelectromotor and a power system for providing electric power to theelectromotor drive of the vehicle, which power system is provided with:first energy storage means for storing a quantity of energy and having apower discharge capacity; first measuring means for measuring the energycondition of the first energy storage means; first power generatingmeans for generating electric power; a computer system, operationallyconnected to the actuator for receiving a power demand, to the firstmeasuring means for receiving a first energy condition value, and to thefirst power generating means, wherein the first energy storage means areoperationally connected to the electromotor for supplying power thereto,the first power generating means are operationally connected to thefirst energy storage means for supplying energy thereto, and thecomputer system controls the power supplied by the first powergenerating means so that the energy storage means are able to providethe electromotor drive with the power the electric drive needs fordriving the vehicle.
 2. Vehicle according to claim 1 wherein thecomputer system controls the power supplied by the first powergenerating means in order for the first energy condition value not todrop below a set first threshold value.
 3. Vehicle according to claim 2,wherein the computer system is adapted for adjusting the threshold valueduring the ride.
 4. Vehicle according to claim 3, wherein the computersystem has historical power data and/or energy data of the vehicle atits disposal, and is adapted for adjusting the threshold value on thebasis of said historical power data and/or energy data.
 5. Vehicleaccording to claim 3, wherein the computer system has a set rideduration at its disposal, and is adapted for adjusting the thresholdvalue on the basis of the set ride duration.
 6. Vehicle according toclaim 1, wherein the first energy storage means comprise at least onebattery.
 7. Vehicle according to claim 1, further comprising secondenergy storage means, preferably capacitors, preferably comprising,several capacitors each having a capacity of at least 800 F and havingan energy storage capacity of at least 2 KJ, wherein the second energystorage means are operationally connected to the first energy storagemeans for receiving electric power therefrom or supplying electric powerthereto.
 8. Vehicle according to claim 1, further comprising secondenergy storage means, preferably capacitors, preferably comprisingseveral capacitors, each having a capacity of at least 800 F and anenergy storage capacity of at least 2 KJ, wherein the second energystorage means are operationally connected via the actuator to theelectric drive for discharging electric power thereto.
 9. Vehicleaccording to claims 7 or 8, further comprising a charging deviceconnected between the first power generating means and the first energystorage means.
 10. Vehicle according to claim 9, further comprising acontrol device, connected to the first energy storage means and thecharging device.
 11. Vehicle according to claim 1, comprising severalfirst energy storage means, parallel interconnected.
 12. Vehicleaccording to claim 11, comprising several second energy storage means,each second energy storage means being connected to one of the firstenergy storage means.
 13. Vehicle according to claim 11 or 12, whereineach first energy storage means comprises its own charging device andits own control device.
 14. Vehicle according to claim 11, wherein thefirst power generating means are parallel connected to the first energystorage means.
 15. Vehicle according to claim 1, wherein the firstenergy storage means or the several energy storage means are eachconnected via a converter with a solar panel.
 16. Vehicle according toclaim 1, wherein the electromotor is a synchronous motor havingpermanent magnets, provided with a control system for controlling theoperation of the electromotor and accommodated in the electromotor. 17.Vehicle according to claim 1, furthermore provided with at least onewheel that is directly driven by means of the electromotor, preferablyan electromotor in the wheel, which preferably is provided with liquidcooling and a control system for the electromotor accommodated in saidelectromotor and specific with the liquid cooling the cooling ofwindings and the control system.
 18. Vehicle according to claim 1,wherein the first power generating means comprise a generator providedwith a combustion engine.
 19. Vehicle according to claim 1, furthercomprising second measuring means for measuring the power condition ofthe first power generating means, and wherein the computer system isfurther operationally connected to the second measuring means forreceiving a second power condition value, and the computer systemfurther sets the power supplied by the first power generating meanswhile using the second power condition value.
 20. Vehicle comprising: atleast one electromotor for driving the vehicle; an actuator forcontrolling the supply of electric power to the electromotor and a powersystem for providing electric power to the electromotor drive of thevehicle, which power system is provided with: a first energy storage forstoring a quantity of energy and having an electric power dischargecapacity; a first energy meter for measuring an energy condition of thefirst energy storage; a first power generating unit for generatingelectric power; a computer system, operationally connected to theactuator for receiving a power demand, to the first energy meter forreceiving a first energy condition value therefrom, and connected to thefirst power generating unit, wherein the first energy storage isoperationally connected to the electromotor for supplying power thereto,the first power generating unit is operationally connected to the energystorage for supplying power thereto for supplementing the energy, andthe computer system controls the power supplied by the first powergenerating unit so that the energy storage is able to provide theelectromotor drive with sufficient power for driving the vehicle. 21.Vehicle according to claim 20, wherein the computer system activates thepower generating unit as long as the first energy condition value isbelow a set first threshold value.
 22. Vehicle according, to claim 20,further provided with a power meter for measuring a power condition ofthe first power generating unit, wherein the computer system isfurthermore operationally connected to the power meter for receiving apower value therefrom, and the computer system further sets the powersupplied by the power generating unit to the energy storage adjusted tothe power value.
 23. Method for controlling the electric power for anelectric drive of a vehicle, wherein a first energy storage supplieselectric power to the electric drive, a first power generating unitsupplies electric power to the first energy storage, and wherein anenergy condition of the first energy storage determines the power to besupplied by the power generating unit.
 24. Power system for supplyingelectric power to a vehicle having an electric drive, wherein an energycondition of a first energy storage unit determines the electric powerto be supplied by a power generating unit to the energy storage unit.25. Power system according to claim 24, wherein a power dischargecapacity of the first energy storage determines the power dischargecapacity of the power system.
 26. Power system according to claim 25,wherein the power discharge capacity of the first energy storage almostcorresponds to the power discharge capacity of the power system. 27.Vehicle comprising an electric drive, preferably comprising at least oneelectromotor, having a peak input power and a rated input power anaccumulator unit having an energy storage capacity and a power dischargecapacity sufficient for supplying the peak input power during a timespan necessary for accelerating from a standstill to a cruising speed ofthe vehicle, and a generator provided with a combustion engine having arated power discharge approximately corresponding to the rated inputpower of the electric drive.
 28. Vehicle according to the precedingclaim, wherein the energy storage capacity of the accumulator unit issufficient for providing the electric drive of the vehicle withsufficient power for maintaining the cruising speed during avehicle-specific driving time.
 29. Vehicle according to claim 28,wherein the vehicle-specific driving time is at least 15 minutes,preferably at least 60 minutes.
 30. Power system for providing anelectric drive of a vehicle with electric power, comprising an energystorage provided with an energy meter for measuring an energy conditionof the energy storage, and a power generating unit provided with asetting unit for setting the electric power to be supplied by the powergenerating unit, wherein the energy storage supplies electric power tothe electric drive, the power generating unit supplies electric power tothe energy storage, and the setting unit is operationally connected tothe energy meter and sets the electric power to be supplied by the powergenerating unit to the energy storage on the basis of the energycondition of the energy storage.
 31. Power system according to claim 30,wherein the setting unit is connected to the energy meter via thecomputer system that controls the setting unit.
 32. Vehicle comprising:at least one electromotor for driving the vehicle; an actuator forcontrolling the supply of electric power to the electromotor and a powersystem for providing electric power to the drive of the vehicle, whichpower system is provided with: first power storage means for storingenergy for supplying electric power; first measuring means for measuringthe power condition of the first power storage means; first powergenerating means for generating electric power; second measuring meansfor measuring the power condition of the first power generating means; acomputer system, operationally connected to the actuator for receiving apower demand, to the first measuring means and second measuring meansfor receiving first and second energy condition values, and to the firstpower generating means, wherein the first power storage means areoperationally connected to the electromotor for supplying power thereto,the first power generating means are operationally connected to thepower storage means for supplying power thereto, and the computer systemactivates the power generating means as long as the first powercondition value drops below a predetermined first threshold value.33.-34. (canceled)